Thermochromic Behavior of Azobenzene-based Coordination Polymer with Reversible Breathing Process

摘要

abstract_textpA multiple stimuli-responsive coordination polymer, namely, Zn(H2O)(6)Zn4Na2L4(H2O)(12)(H2O)(12) (1) (H3L = 5-(4-Sulfophenylazo) salicylic acid), was synthesized by a simple hydrothermal method. It reveals a 2D elastic layer-structured framework, forming a three-dimensional (3D) interlinked networks driven by extensive pi...pi stacking interactions. Removing water molecules by heating or vacuum freeze drying, it not only shows a reversible thermo-chromism but also exhibits a selective gas absorption and breathing effect. In addition, this material exhibits skeleton stability under reversible dehydration/hydration. The reversible thermochromic behaviour is mainly attributed to the change of the coordination environment of Zn2+ ions during the dehydration/hydration process. Furthermore, the film of 1 on the polylactic acid (PLA) support displayed similar reversible thermochromic behaviour with high sensitivity (large color-change and rapid response upon cooling or heating), promoting its application in switching fibres and devices, and naked-eye colorimetric sensor in the future./p/abstract_text